1. Field of the Invention
The invention relates to a nickel metal hydride/nickel cadmium secondary battery charger, and more particularly to a battery charger structure that allows an electric plug to be rotated and folded within 180 degrees and stored in the battery charger.
2. Description of the Related Art
As science and technology advance, electronic products including digital cameras, mobile phones, Game Boy and PDA become popular, and all of these 3C electronic products require dry cells for supplying electric power.
However, a dry cell can be divided into two types: a primary dry cell and a secondary dry cell, wherein the primary dry cell will be discarded after the power is exhausted, and thus a primary dry cell not only increases a user's cost, but also causes problems to environmental protection. Therefore, the secondary dry cell that can be recharged become a mainstream, but the major issue of using a secondary dry cell for the 3C products resides on finding a place outdoors to charge the dry cells after the electric power of the dry cells is exhausted.
Although there are many chargers available for charging a battery in a car by inserting a power supply plug with a conductive connecting cable into a cigarette lighter socket as disclosed in U.S. Pat. No. 5,839,919 and US2003/0062873A1 to overcome the problem of charging a battery outdoors, the foregoing two patented inventions disclosed ways of charging the battery of a mobile phone, but they cannot charge secondary dry cells. Further, U.S. Pat. No. 5,686,811 disclosed a way of charging secondary dry cells, but it comes with a large volume that occupies too much space, and its conductive connecting cable cannot be connected to the cigarette lighter socket in a car.
Therefore, finding a way of improving the battery charger and charging a battery conveniently in a car without occupying much space to facilitate its carrying demand immediate attentions and feasible solutions.